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电子档案长期保存中的格式迁移策略研究——以PDF/A与XML格式为例
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作者 赵阳 《机电兵船档案》 2026年第1期65-67,共3页
在数字技术快速发展的背景下,电子档案长期保存面临格式过时、技术环境迭代等挑战,格式迁移成为保障电子档案真实性、完整性、可访问性与可用性的关键手段。PDF/A和XML作为电子档案保存的重要格式,在迁移需求与逻辑上存在差异。本文针... 在数字技术快速发展的背景下,电子档案长期保存面临格式过时、技术环境迭代等挑战,格式迁移成为保障电子档案真实性、完整性、可访问性与可用性的关键手段。PDF/A和XML作为电子档案保存的重要格式,在迁移需求与逻辑上存在差异。本文针对这两种格式,分析电子档案格式迁移现状及两者迁移痛点,构建针对性迁移策略及协同应用框架,并探讨迁移实践中的挑战与优化建议。研究旨在为电子档案格式迁移实践提供科学参考,以提升电子档案长期保存质量。 展开更多
关键词 电子档案 长期保存 格式迁移 pdf/A XML
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Estimates for p-adic fractional integral operator with rough kernels on grand p-adic Herz-type spaces
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作者 XIA Xiaoxi ZHOU Jiang 《中山大学学报(自然科学版)(中英文)》 北大核心 2026年第2期153-159,共7页
The goal of this paper is to establish the boundedness of the p-adic fractional integral operator with rough kernel I_(β,Ω′)^(p)and its commutators generated by b∈Λ_(γ)(Q_(p)^(n))(0<γ<1)and the I_(β,Ω′... The goal of this paper is to establish the boundedness of the p-adic fractional integral operator with rough kernel I_(β,Ω′)^(p)and its commutators generated by b∈Λ_(γ)(Q_(p)^(n))(0<γ<1)and the I_(β,Ω′)^(p) on grand p-adic Herz spaces. 展开更多
关键词 Lipschitz spaces grand p-adic Herz spaces p-adic fractional integral operator COMMUTATORS
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Lipschitz Estimates for the Commutators of Fractional Hardy and Hardy-Littlewood-Pólya Operators on Grand p-adic Variable Herz Spaces
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作者 常云鹏 武江龙 《数学进展》 北大核心 2026年第2期419-430,共12页
In this article,we prove the boundedness for commutators of fractional Hardy and Hardy-Littlewood-Pólya operators on grand p-adic variable Herz spaces,where the symbols of the commutators belong to Lipschitz spaces.
关键词 p-adic field fractional Hardy operator Hardy-Littlewood-Pólya operator grand variable Herz space commutator
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Fractional calculus approach to RT-IN enzymatic competition in modulating HIV replication dynamics
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作者 Tushar Ghosh Oluwole Daniel Makinde +1 位作者 WANG Shu Priti Kumar Roy 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期225-254,共30页
HIV infection continues to pose a significant global health challenge,with subSaharan Africa bearing a disproportionate burden.The replication cycle of HIV is fundamentally driven by intricate molecular interactions.T... HIV infection continues to pose a significant global health challenge,with subSaharan Africa bearing a disproportionate burden.The replication cycle of HIV is fundamentally driven by intricate molecular interactions.This study investigates the competitive biochemical interplay between reverse transcriptase(RT)and integrase(IN)enzymes,employing a fractional calculus framework to model their mutual inhibitory effects.Through the application of fixed-point theory and Picard stability analysis,the existence,uniqueness,and stability of the fractional-order system are rigorously established.The role of RT-IN enzymatic competition in influencing HIV replication dynamics is elucidated through global sensitivity analysis using Latin Hypercube Sampling.Furthermore,the model incorporates memory-dependent characteristics by examining three distinct fractional operators,namely,the Caputo,Caputo-Fabrizio,and Atangana-Baleanu operators in the Caputo sense,thereby elucidating their respective influences on system behavior.The Atangana-Baleanu operator,in particular,demonstrates an enhanced capacity to capture the complex,synergistic processes underpinning HIV progression.This research provides a critical nexus between molecular virology and applied mathematics,offering foundational insights for the advancement of more precise and targeted therapeutic strategies against HIV. 展开更多
关键词 HIV biochemical interaction physical interaction fractional calculus Sumudu transformation LHS PRCC
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A Fractional-Order Study for Bicomplex Haemorrhagic Infection in Several Populations Conditions
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作者 Muhammad Farman Muhammad Hashir Zubair +2 位作者 Hua Li Kottakkaran Sooppy Nisar Mohamad Hafez 《Computer Modeling in Engineering & Sciences》 2026年第1期926-953,共28页
Lassa Fever(LF)is a viral hemorrhagic illness transmitted via rodents and is endemic in West Africa,causing thousands of deaths annually.This study develops a dynamic model of Lassa virus transmission,capturing the pr... Lassa Fever(LF)is a viral hemorrhagic illness transmitted via rodents and is endemic in West Africa,causing thousands of deaths annually.This study develops a dynamic model of Lassa virus transmission,capturing the progression of the disease through susceptible,exposed,infected,and recovered populations.The focus is on simulating this model using the fractional Caputo derivative,allowing both qualitative and quantitative analyses of boundedness,positivity,and solution uniqueness.Fixed-point theory and Lipschitz conditions are employed to confirm the existence and uniqueness of solutions,while Lyapunov functions establish the global stability of both disease-free and endemic equilibria.The study further examines the role of the Caputo operator by solving the generalized power-law kernel via a two-step Lagrange polynomial method.This approach offers practical advantages in handling additional data points in integral forms,though Newton polynomial-based schemes are generally more accurate and can outperform Lagrange-based Adams-Bashforth methods.Graphical simulations validate the proposed numerical approach for different fractional orders(ν)and illustrate the influence of model parameters on disease dynamics.Results indicate that increasing the fractional order accelerates the decline of Lassa fever in both human and rodent populations.Moreover,fractional-order modeling provides more nuanced insights than traditional integer-order models,suggesting potential improvements for medical intervention strategies.The study demonstrates that carefully chosen fractional orders can optimize convergence and enhance the predictive capacity of Lassa fever models,offering a promising direction for future research in epidemiological modeling. 展开更多
关键词 Lassa fever mathematical model caputo fractional operator lyapunov stability
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CT-derived fractional flow reserve combined with atherosclerotic extent to determine long-term outcomes in diabetic patients with coronary artery disease
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作者 Zhi-Qiang WANG Zhen-Nan LI +1 位作者 Zhi-Hui HOU Bin LU 《Journal of Geriatric Cardiology》 2026年第1期27-35,共9页
Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value ... Background There is still limited data on predictive value of coronary computed tomography angiography(CCTA)–derived fractional flow reserve(CT-FFR) for long term outcomes. We examined the long-term prognostic value of CT-FFR combined with CCTA–defined atherosclerotic extent in diabetic patients with coronary artery disease(CAD).Methods A retrospective pooled analysis of individual patient data was performed. Deep-learning-based vessel-specific CTFFR was calculated. All patients enrolled were followed-up for at least 5 years. Predictive abilities for major adverse cardiac events(MACE) were compared among three models(model 1), constructed using clinical variables;model 2, model 1+CCTA–derived atherosclerotic extent(Leiden risk score);and model 3, model 2+CT-FFR.Results A total of 480 diabetic patients [median age, 61(55–66) years;52.9% men] were included. During a median follow-up time of 2197(2126–2355) days, 55 patients(11.5%) experienced MACE. In multivariate-adjusted Cox models, Leiden risk score(HR: 1.06;95% CI: 1.01–1.11;P = 0.013) and CT-FFR ≤ 0.80(HR: 6.54;95% CI: 3.18–13.45;P < 0.001) were the independent predictors. The discriminant ability was higher in model 2 than in model 1(C-index, 0.75 vs. 0.63;P < 0.001) and was further promoted by adding CT-FFR to model 3(C-index, 0.81 vs. 0.75;P = 0.002). Net reclassification improvement(NRI) was 0.19(P = 0.009) for model 2 beyond model 1. Of note, adding CT-FFR to model 3 also exhibited significantly improved reclassification compared with model 2(NRI = 0.14;P = 0.011).Conclusion In diabetic patients with CAD, CT-FFR provides robust and incremental prognostic information for predicting longterm outcomes. The combined model exhibits improved prediction abilities, which is beneficial for risk stratification. 展开更多
关键词 fractional flow reserve ct ffr coronary artery disease cad methods tomography angiography ccta derived coronary artery disease atherosclerotic extent fractional flow reserve diabetic patients coronary computed tomography angiography
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Molecular composition of water soluble fraction of petroleum products and crude oils:Insights into groundwater contamination potential and environmental forensics
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作者 Wang Yu Yuruo Wan +3 位作者 Wei Zhou Jiayi An Liting Tian Jie Ma 《Journal of Environmental Sciences》 2026年第1期437-444,共8页
Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.Th... Petroleum leakage is a major groundwater contamination source,with chemical composition of water soluble fractions(WSFs)from diverse oil sources significantly impacting groundwater quality and source identification.The aim of this study was to assess impact of 15 diverse oils on groundwater quality and environmental forensics based on oil-water equilibrium experiments.Our results indicate that contamination of groundwater by gasoline and naphtha is primarily attributed to volatile hydrocarbons,while pollution from diesel,kerosene,and crude oil is predominantly from non-hydrocarbons.Rapid determination of the extent of non-hydrocarbon pollution in WSFs was achieved through a new quantitative index.Gasoline and naphtha exhibited the highest groundwater contamination potential while kerosene and light crude oils were also likely to cause groundwater contamina-tion.Although volatile hydrocarbons in the WSFs of diesel and jet fuel do not easily exceed current regulatory standards,unregulated non-hydrocarbons may pose a more severe contamination risk to groundwater.Notably,the presence of significant benzene and toluene,hydrogenation and alkylation products(e.g.,C4-C5 alkylben-zenes,alkylindenes,alkyltetralins,and dihydro-indenes),cycloalkanes in WSFs can effectively be utilized for preliminary source identification of light distillates,middle distillates,and crude oils,respectively. 展开更多
关键词 Petroleum hydrocarbons Water soluble fraction Contaminated sites Groundwater contamination Source identification
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Prediction of lithium content in typical mountainous clay in Xinjiang,China using fractional derivatives and feature extraction
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作者 JIANG Guo CUI Shichao +6 位作者 CHEN Xi CHEN Xi WANG Jinlin CHEN Tao ZHOU Shuguang ZHANG Zhengfeng XU Xiaozhi 《Journal of Mountain Science》 2026年第2期545-558,共14页
Lithium(Li)is an‘emerging'environmental pollutant,especially in soil,which is a great concern because it can endanger human health through the food chain.Compared with traditional chemical analyses,hyperspectral ... Lithium(Li)is an‘emerging'environmental pollutant,especially in soil,which is a great concern because it can endanger human health through the food chain.Compared with traditional chemical analyses,hyperspectral techniques have achieved many exciting results in soil metal monitoring due to their advantages of being fast and non-destructive.However,insufficient attention has been paid to lithium in soil,and the feasibility of its estimation using hyperspectral techniques needs to be investigated.We studied 97 soil samples from claytype lithium mines in the Ertanggou area of the East Tianshan Mountains of Xinjiang to explore the effects of spectral resolution,fractional order derivatives(FOD),and characteristic band selection on the estimation accuracy of clay Li content,to obtain a fast and effective method for estimating clay Li content.Finally,we developed a new method for rapid and nondestructive estimation of soil lithium content.We have obtained some important results from the study.Spectral resolution exerts a significant impact on model performance,and its reduction usually leads to a decline in model performance.For the full band,the models constructed with low-order derivatives were superior to those with high-order derivatives,and the best model was obtained at the 0.4-order derivative(coefficient of determination(R^(2))and relative predictive deviation(RPD)of 0.777 and 2.118,respectively).In the characteristic bands,the lower order is sensitive to the visible-near-infrared range,and the higher order is sensitive to the short-wave infrared range,and the model constructed with the higher-order derivatives outperforms the lower-order derivatives.In this study,the combination of FOD and Random Forest(RF)can significantly improve the model performance,with R^(2),Relative Root Mean Squared Error(RRMSE),and RPD being 0.849,1.526,and 2.574,respectively.Therefore,this research provides a theoretical basis and technical reference for imaging hyperspectral exploration of anomalous areas of clay-type Li resources. 展开更多
关键词 Hyperspectral remote sensing fractional order Derivatives Random Forest LITHIUM Soil pollutant
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基于HTML2PDF的校园电子签章系统研究与实现
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作者 赵通 曾志华 卢笙 《信息技术与信息化》 2026年第1期52-55,共4页
针对传统纸质文档管理效率低下,安全性不足等问题。文章提出一种基于HTML转PDF(HTML2PDF)的数字化解决方案,实现校园各类证明文档的电子化转换与无需认证机构(CA )证书的电子签章、验章。通过采用超文本标记语言(HTML)构建的动态内容,... 针对传统纸质文档管理效率低下,安全性不足等问题。文章提出一种基于HTML转PDF(HTML2PDF)的数字化解决方案,实现校园各类证明文档的电子化转换与无需认证机构(CA )证书的电子签章、验章。通过采用超文本标记语言(HTML)构建的动态内容,转换为具备高保真打印特性和跨平台共享能力的便携式文档格式(PDF),构建了完整的电子签章系统架构。实验验证表明,该技术方案有效解决了纸质文档管理的核心痛点,为校园电子签章系统的工程化实现奠定了技术基础。 展开更多
关键词 校园管理 HTML2pdf 电子签章 认证机构(CA)
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Land use type shapes carbon pathways in Tibetan alpine ecosystems:Characterization of ^(13)C abundance in aggregates and density fractions
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作者 Xin Wan Dangjun Wang +7 位作者 Junya Li Shuaiwen Zhang Linyang Li Minghui He Zhiguo Li Hao Jiang Peng Chen Yi Liu 《Journal of Integrative Agriculture》 2026年第2期448-459,共12页
Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In ... Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions. 展开更多
关键词 land use type soil aggregate density fractions carbon transfer Tibetan Plateau
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Global Optimization Algorithm for Minimizing Linear Fractional Programming
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作者 ZHAO Peng SHEN Pei-ping ZHONG Zhe-wei 《Chinese Quarterly Journal of Mathematics》 2026年第1期50-59,共10页
In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,w... In this paper,we study a class of Linear Fractional Programming on a nonempty bounded set,called the Problem(LFP),and design a branch and bound algorithm to find the global optimal solution of the problem(LFP).First,we convert the problem(LFP)to the equivalent problem(EP2).Secondly,by applying the linear relaxation technique to the problem(EP2),the linear relaxation programming problem(LRP2Y)was obtained.Then,the overall framework of the algorithm is given,and the convergence and complexity of the algorithm are analyzed.Finally,experimental results are listed to illustrate the effectiveness of the algorithm. 展开更多
关键词 Global optimization Linear fractional Programming Branch and bound algorithm Linear relaxation
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POHOZAEV MINIMIZERS FOR FRACTIONAL CHOQUARD EQUATIONS WITH MASS-SUPERCRITICAL NONLINEARITY
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作者 Liju WU Jiankang XIA 《Acta Mathematica Scientia》 2026年第1期164-188,共25页
We investigate the constrained fractional Choquard equation■where m>0,N>2s with s∈(0,1)being the order of the fractional Laplacian operator and I_(α)forα∈(0,N)denotes the Riesz potential.The parameterμ∈ℝa... We investigate the constrained fractional Choquard equation■where m>0,N>2s with s∈(0,1)being the order of the fractional Laplacian operator and I_(α)forα∈(0,N)denotes the Riesz potential.The parameterμ∈ℝappears as a Lagrange multiplier.By imposing general mass-supercritical conditions on F,we confirm the existence of normalized solutions that characterize the global minimizer on the Pohozaev manifold.Our proof does not depend on the assumption that all weak solutions satisfy the Pohozaev identity,a challenge that remains unsolved for this doubly nonlocal equation. 展开更多
关键词 nonlinear fractional Choquard equation double nonlocality super-critical mass normalized solutions Pohozaev minimizer
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Tribological Properties and Wear Mechanisms of SiCp/6092Al Composites with Different Volume Fractions
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作者 WANG Dongliang DOU Jianming +2 位作者 ZHANG Jilin YI Xiangbin MA Furong 《Journal of Wuhan University of Technology(Materials Science)》 2026年第2期323-332,共10页
SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing... SiCp-reinforced 6092Al composites with volume fractions of 25%and 60%were prepared using a powder metallurgy method.Their friction and wear characteristics were analyzed using a reciprocating friction and wear testing machine under loads of 20 to 50 N against YG6 cemented carbide.The experimental results show that the friction coefficients of all samples increase with increasing load.The 25vol%composite exhibits the lowest friction coefficient(0.1669-0.2716),while the 60vol%composite exhibits the highest(0.3237-0.3990),with the 6092 aluminum alloy falling between the two.The wear volume and specific wear rate also increase with load,but the composites with a higher Si C content demonstrate smaller increments,with the 60vol%composite exhibiting superior wear resistance.Under a 30 N load,the wear scars of the 60vol%composite show a significant increase in the contents of elements such as C,Co,W,and O,indicating more severe wear of the counterpart material.Scanning electron microscopy(SEM)reveals wear mechanisms including adhesive wear,two-body sliding and three-body rolling wear of particles,and delamination. 展开更多
关键词 SiCp/6092Al composites wear mechanisms different volume fractions tribological properties
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Developments in the applications of density functional theory to fractional quantum Hall systems
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作者 Yi Yang Yayun Hu Zi-Xiang Hu 《Communications in Theoretical Physics》 2026年第2期220-230,共11页
The fractional quantum Hall effect remains a captivating area in condensed matter physics,characterized by strongly correlated topological order,which manifests as fractionalized excitations and anyonic statistics.Num... The fractional quantum Hall effect remains a captivating area in condensed matter physics,characterized by strongly correlated topological order,which manifests as fractionalized excitations and anyonic statistics.Numerical simulations,such as exact diagonalization,density matrix renormalization groups,matrix product states,and Monte Carlo methods are essential for examining the properties of strongly correlated systems.Recently,density functional theory has been employed in this field within the framework of composite fermion theory.This paper systematically evaluates how density functional theory approaches have addressed fundamental challenges in fractional quantum Hall systems,including ground state and low-energy excitations.Special attention is given to the insights provided by density functional theory regarding composite fermion behavior,edge effects,and the nature of fractional charge and magnetoroton excitations.The discussion critically examines both the advantages and limitations of these approaches,while highlighting the productive interplay between numerical simulations and theoretical models.Future directions are explored,particularly the promising potential of time-dependent density functional theory for modeling non-equilibrium dynamics in quantum Hall systems. 展开更多
关键词 composite fermions fractional quantum Hall effect density functional theory low-lying excitations topological physics
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MRI腰椎骨髓脂肪定量参数PDFF结合骨代谢标志物在评估骨质疏松症中的临床价值
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作者 陈晓丽 马洪宇 +2 位作者 石少聪 王国庆 张建保 《中国CT和MRI杂志》 2026年第2期156-159,共4页
目的探讨磁共振成像(MRI)腰椎骨髓脂肪定量参数质子密度脂肪分数(PDFF)结合骨代谢标志物在评估骨质疏松症(OP)中的临床价值。方法选取慢性腰痛患者119例,病例收集时间为2024年1月至2025年3月,均来源于我院,患者均行腰椎定量电子计算机... 目的探讨磁共振成像(MRI)腰椎骨髓脂肪定量参数质子密度脂肪分数(PDFF)结合骨代谢标志物在评估骨质疏松症(OP)中的临床价值。方法选取慢性腰痛患者119例,病例收集时间为2024年1月至2025年3月,均来源于我院,患者均行腰椎定量电子计算机断层扫描(QCT)及MRI腰椎骨髓脂肪定量技术检查,根据患者骨质状态分为骨量正常、骨量减少和OP组,各为29、43和47例。收集患者资料,比较各组骨密度(BMD)值、MRI腰椎骨髓脂肪定量参数PDFF及血清25-羟基维生素D_(3)[25(OH)D_(3)]、Ⅰ型前胶原氨基端前肽(PINP)、β-胶原特殊序列(β-CTX)、骨钙素(OC)水平,分析MRI腰椎骨髓脂肪定量参数PDFF与骨代谢标志物的相关性和MRI腰椎骨髓脂肪定量参数PDFF、骨代谢标志物与BMD的相关性,并分析MRI腰椎骨髓脂肪定量参数PDFF结合骨代谢标志物对OP的诊断价值。结果BMD值及25(OH)D_(3)、PINP、OC在骨量正常、骨量减少、OP组之间逐渐降低(P<0.05),而PDFF及β-CTX水平在三组间逐渐升高(P<0.05)。PDFF与β-CTX呈正相关,与25(OH)D_(3)、PINP、OC呈负相关(P<0.05);BMD值与PDFF、β-CTX呈负相关,与25(OH)D_(3)、PINP、OC呈正相关P<0.05)。PDFF及25(OH)D_(3)、PINP、β-CTX、OC联合检测诊断OP的AUC值为0.932,高于各指标单独检测(0.794、0.847、0.736、0.800、0.781,P<0.05)。结论OP患者MRI腰椎骨髓脂肪定量参数PDFF及血清β-CTX水平较高,而BMD值及血清25(OH)D_(3)、PINP、OC水平较低,上述指标之间存在一定联系,且MRI腰椎骨髓脂肪定量参数PDFF结合骨代谢标志物在评估OP中具有一定优势。 展开更多
关键词 骨质疏松症 磁共振成像 质子密度脂肪分数 骨代谢 相关性 诊断价值
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A Deterministic and Stochastic Fractional-Order Model for Computer Virus Propagation with Caputo-Fabrizio Derivative:Analysis,Numerics,and Dynamics
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作者 Najat Almutairi Mohammed Messaoudi +1 位作者 Faisal Muteb K.Almalki Sayed Saber 《Computer Modeling in Engineering & Sciences》 2026年第3期806-843,共38页
This paper introduces a novel fractional-order model based on the Caputo-Fabrizio(CF)derivative for analyzing computer virus propagation in networked environments.The model partitions the computer population into four... This paper introduces a novel fractional-order model based on the Caputo-Fabrizio(CF)derivative for analyzing computer virus propagation in networked environments.The model partitions the computer population into four compartments:susceptible,latently infected,breaking-out,and antivirus-capable systems.By employing the CF derivative—which uses a nonsingular exponential kernel—the framework effectively captures memory-dependent and nonlocal characteristics intrinsic to cyber systems,aspects inadequately represented by traditional integer-order models.Under Lipschitz continuity and boundedness assumptions,the existence and uniqueness of solutions are rigorously established via fixed-point theory.We develop a tailored two-step Adams-Bashforth numerical scheme for the CF framework and prove its second-order accuracy.Extensive numerical simulations across various fractional orders reveal that memory effects significantly influence virus transmission and control dynamics;smaller fractional orders produce more pronounced memory effects,delaying both infection spread and antivirus activation.Further theoretical analysis,including Hyers-Ulam stability and sensitivity assessments,reinforces the model’s robustness and identifies key parameters governing virus dynamics.The study also extends the framework to incorporate stochastic effects through a stochastic CF formulation.These results underscore fractional-order modeling as a powerful analytical tool for developing robust and effective cybersecurity strategies. 展开更多
关键词 Caputo-Fabrizio derivative fractional-order computer virus model stochastic fractional dynamics Adams-Bashforth scheme Hyers-Ulam stability sensitivity analysis cyber-epidemiology memory effects nonsingular kernel
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The Immunomodulatory,Anti-Tumor,and Metabolic Regulatory Effects of Fraction D of Polysaccharide from Grifola frondosa:Clinical Experiments and Mechanistic Insights
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作者 Nurfarih Hanna Mohd Zarif Fikri Bin Mohd +1 位作者 Muhammad Nabil Fikri Bin Mohd Nurfarazuna Binti Mohd Fadrol 《Proceedings of Anticancer Research》 2026年第1期84-93,共10页
Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical eff... Grifola frondosa(Maitake)is traditionally valued for its health benefits,with polysaccharides being key bioactive components.This paper investigates a specific subfraction,Fraction D(GFP-D),evaluating its clinical effects and mechanisms in immune enhancement,adjunctive anti-tumor activity,and regulation of glucose/lipid metabolism.Three clinical trials were conducted.In an immune study,120 healthy volunteers(CD4+T cell count 500–1000 cells/μL)received 150 mg/day GFP-D for 8 weeks,resulting in significant increases in CD4+T cells(from 632±95 to 812±108 cells/μL,28.5%increase,within the physiological activation range),CD4+/CD8+ratio,NK cell activity,IL-2,and IFN-γ(all P<0.001 vs.placebo).An anti-tumor study with 80 advanced cancer patients(stratified by age,tumor stage,and histotype)showed that adding 1000 mg/day GFP-D to chemotherapy improved objective response rate(52.5%vs.30.0%,P=0.036,95%CI:1.02–3.87),one-year progression-free survival(55.8%vs.33.3%,P=0.022),and preserved immune parameters versus chemotherapy alone.A metabolic study in 90 type 2 diabetes patients found that 400 mg/day GFP-D for 12 weeks significantly lowered fasting glucose,HbA1c,total cholesterol,triglycerides,and LDL-C,while raising HDL-C(from 1.0±0.2 to 1.2±0.2 mmol/L,20%increase,supported by increased AMPK phosphorylation).Mechanistically,immune enhancement involves macrophage/dendritic cell activation via Dectin-1/TLR4 receptors(confirmed by increased receptor expression and downstream signaling molecules),promoting cytokine-driven T/NK cell responses.Anti-tumor effects stem from immunomodulation,direct induction of cancer cell apoptosis(via mitochondrial/caspase pathways,verified by increased Bax/Bcl-2 ratio and caspase-3 activation),and angiogenesis inhibition by downregulating VEGF.Metabolic benefits are linked to AMPK pathway activation in liver/muscle(confirmed by increased p-AMPK/AMPK ratio),enhancing glucose uptake and inhibiting gluconeogenesis/lipogenesis,alongside modulation of gut microbiota(increased Bifidobacterium and Lactobacillus abundance).All trials reported no severe adverse events related to GFP-D;liver/kidney function parameters(ALT,AST,creatinine,urea nitrogen)remained within normal ranges throughout the intervention.Collectively,GFP-D emerges as a multi-functional bioactive agent with substantial therapeutic potential. 展开更多
关键词 Grifola frondosa Maitake polysaccharide fraction D Immune modulation Adjunctive cancer therapy Glycemic control Lipid metabolism Clinical trial Mechanism of action
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基于MRI-PDFF分析探讨定量CT对不同程度脂肪性肝病的诊断价值
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作者 杭也奇 单华 余滔 《中国中西医结合影像学杂志》 2026年第2期145-148,共4页
目的:基于MRI测定的质子密度脂肪分数(MRI-PDFF)分析探讨定量CT诊断不同程度脂肪性肝病的价值。方法:回顾性收集40例行肝脏MRI-PDFF分析患者的临床及影像资料。根据MRI-PDFF分析结果,将患者分为正常组10例,轻度组17例和中重度组13例。... 目的:基于MRI测定的质子密度脂肪分数(MRI-PDFF)分析探讨定量CT诊断不同程度脂肪性肝病的价值。方法:回顾性收集40例行肝脏MRI-PDFF分析患者的临床及影像资料。根据MRI-PDFF分析结果,将患者分为正常组10例,轻度组17例和中重度组13例。将CT横断位薄层图像导入Bone’s FRAX定量CT软件,在第一肝门层面勾画ROI,分别行软组织脂肪含量分析和肝脾CT值比值分析。绘制ROC曲线,评价两者诊断轻度、中重度脂肪性肝病的效能。结果:年龄、性别在正常组、轻度组及中重度组中差异均无统计学意义(均P>0.05)。软组织脂肪含量和肝脾CT值比值诊断轻度脂肪性肝病的AUC分别为0.632和0.674,诊断中重度脂肪性肝病的AUC分别为0.855和0.825。结论:定量CT尤其是肝脾CT值比值,在诊断中重度脂肪性肝病中具有一定的临床价值,可作为MRI的一种便捷、有效的补充或替代工具,但其对轻度脂肪性肝病的诊断价值有限。 展开更多
关键词 脂肪性肝病 磁共振成像 质子密度脂肪分数 体层摄影术 X线计算机 定量分析
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A_(α)-Spectral Conditions for(a,b,k)-Factor-Critical Graphs and Fractional ID-[a,b]-Factor-Critical Covered Graphs
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作者 Yonglei CHEN Fei WEN 《Journal of Mathematical Research with Applications》 2026年第1期1-12,共12页
In this paper,we first give a sufficient condition for a graph being fractional ID-[a,b]-factor-critical covered in terms of its independence number and minimum degree,which partially answers the problem posed by Sizh... In this paper,we first give a sufficient condition for a graph being fractional ID-[a,b]-factor-critical covered in terms of its independence number and minimum degree,which partially answers the problem posed by Sizhong Zhou,Hongxia Liu and Yang Xu(2022).Then,an A_(α)-spectral condition is given to ensure that G is a fractional ID-[a,b]-factor-critical covered graph and an(a,b,k)-factor-critical graph,respectively.In fact,(a,b,k)-factor-critical graph is a graph which has an[a,b]-factor for k=0.Thus,these above results extend the results of Jia Wei and Shenggui Zhang(2023)and Ao Fan,Ruifang Liu and Guoyan Ao(2023)in some sense. 展开更多
关键词 A_(α)-spectral radius (a b k)-factor fractional(g f)-factor ID-factor-critical graph independence number
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基于大模型的PDF文档转换实践
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作者 李兴福 《科学与信息化》 2025年第15期35-38,共4页
PDF(便携式文档格式)是由Adobe公司在1993年推出的文件格式,其可以在任意设备或操作系统上都能保持一致的排版和格式,是在诸多领域广泛使用的标准化文档格式。然而,在众多特定应用场景下,用户对PDF文件的处理往往需要进行格式转换。随... PDF(便携式文档格式)是由Adobe公司在1993年推出的文件格式,其可以在任意设备或操作系统上都能保持一致的排版和格式,是在诸多领域广泛使用的标准化文档格式。然而,在众多特定应用场景下,用户对PDF文件的处理往往需要进行格式转换。随着人工智能技术的发展,利用大模型技术提供的先进文本处理能力,能够探求全新的PDF文档转换解决方案,推动相关技术与工具的发展变革,进而提升PDF转换的准确性与效率。 展开更多
关键词 大模型 pdf文档转换 OCR MinerU
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